Northumberland County was established in 1772 as the tenth county of Pennsylvania. It is called the “Mother of Counties,” with 29 counties split from it over the years. Northumberland County encompassed as much as 15,000 square miles at its height. Today, it covers 470 square miles of the Susquehanna Valley. The county seat, Sunbury, was also created in 1772, while Shamokin sprouted from the increase in commerce and business in the 1830s.
Industry is intertwined with Northumberland’s history. Anthracite coal was the original natural resource in the early 1800s, used to produce iron. Other profitable industries like silk, dairy, and dress factories soon followed. Coal mining and silk production waned with the Great Depression, to be replaced by oil drilling and synthetic textiles.
Pick Your Adventure in Northumberland County, spend a day at Knoebels Amusement Park, or do your research with the Susquehanna River Valley Visitors Bureau.
As of 2025 the population of Northumberland County is 91,321. The population is expected to shrink to 89,878 by 2030 - a growth rate of -0.32%.
The median age of Northumberland County residents is 45.
The diversity index of Northumberland County is 28.4, meaning that there is a 28% chance that any two people selected out of 100 residents will be of different race or ethnicity from one another.
The average household income in Northumberland County is $78,595 and projected to be $87,046 in 2030. Per capita income is $32,461, projected to be $35,772 in 2030. 1.51% of households – 1,380 – have an income of $200,000 or higher. Average net worth is $691,750 and the average disposable income is $61,413.
There are 43,173 housing units in Northumberland County; 27,372 are owner-occupied, 10,266 are rented, and 5,535 are vacant. The average home value is $241,341, with 1,110 homes built in 2010 or later, and 16,444 built in 1939 or earlier.
There are 2,796 businesses in Northumberland County, employing 32,997 workers and pulling from a labor force of 40,284 age 16 and above. 18,252 workers commute into Northumberland County from outside the county or state. Key industries for the area include:
21,879 residents both live and work in/around Northumberland County. The average travel time is 25.4 minutes. 9% people have a commute of less than 5 minutes while 5.62% commute 90 minutes or more each way. Of commuters, 31,301 drive alone, 3,889 carpool, and 107 take public transportation. 1,677 use other modes of transport such as motorcycle, bicycle, walking, etc. 3,277 residents work from home.
32,399 members of the workforce hold a high school diploma or GED. 6,232 have associates degrees, 9,597 have bachelor’s degrees, and 4,037 hold a graduate or professional degree.
